1. Field of the Invention
The present invention relates to a coupling adapted to be connected to an end portion of a tube made of plastic composite material to be used as a structural member in a structure or the like.
2. Description of the Prior Art
A conventional coupling means for coupling an end portion of a tube made of plastic composite material to be used as a structural member to another member includes a mechanical coupling means or a fastener such as a rivet, bolt and nut. However, in such a mechanical coupling means, when a stress such as a tensile stress is generated between the plastic tube and the other member connected thereto, a stress concentration is generated at a wall surface of the plastic tube at a position around a through fole in which the rivet or the bolt is inserted through the plastic tube, causing breakage of the plastic tube or a reduction in strength as the structural member. There exists another coupling means employing adhesive for bonding the plastic tube to the other member. However, this kind of coupling means has a problem of low and ununiformity of the adhesive strength.